Hope you did well!
These are some tips for maths exams (too late for you now, but oh well):
First thing you should do is read all the questions.
Go through and mark all the ones that you can do easily.
Go through and mark all the ones that you will really really struggle on.
Do all the easy, straightforward ones.
Have a look at the remaining ones unmarked. Do the ones that are worth the most marks, then the ones worth less marks, until you run out of those.
Check how much time you have left. If a long time, try one of the really difficult questions.
When you only have ten or fifteen minutes left, read through your working for the questions you already did and correct any mistakes you find.
End of test.
This way, you don't run out of time before doing all the questions you know how to do (how silly if you don't answer one you could have done easily and miss out on those easy marks), and you don't waste time in ones that are very hard unless you have time to spare, and if you do run out of time part way through them you have used your energy doing the ones worth the most marks FIRST so you can get the most marks for the time you were able to spend.